Effects of melatonin and SkQ1 long-term treatment during aging and development AMD-like retinopathy

Poster (download) Darya V. Telegina1, Oyuna S. Kozhevnikova2, Anzhela Z. Fursova31ICG SB RAS, Novosibirsk, Russia, telegina@bionet.nsc.ru2ICG SB RAS, Novosibirsk, Russia, oidopova@bionet.nsc.ru3ICG SB RAS, Novosibirsk, Russia, anzhellafursova@yandex.ru Melatonin and antioxidant SkQ1 act like mitochondria-targeted antioxidants, which concentrate in mitochondria at relatively high levels and they may prevent mitochondrial damage during retinal aging and development of age-related retinal disease such as age-related macular degeneration (AMD). However, detailed effects of melatonin and SkQ1 on the biochemical mechanisms underlying therapeutic effect of these drugs during retinal aging and AMD progression remain unclear.В  Using Wistar rats with normal aging process and senescence-accelerated OXYS rats, which spontaneously develop a phenotype similar to human age-related disorders including AMD-like retinopathy, we found that treatment of SkQ1 and melatonin decreased the incidence and severity of retinopathy in OXYS rats. In Wistar rats, which do not naturally develop retinopathy, ophthalmoscopic inspections did not reveal pathological alterations in the retina of melatonin and SkQ1-treated rats. SkQ1 decreased p62/SQSTM1 protein but not mRNA levels in both OXYS and Wistar rat\’s retinas as compared of control rats. We observed reduced level of VDAC1 and increased level of glutaminase by long-term treatment of melatonin and SkQ1 in retina of Wistar rats but not OXYS rats. Taken together, our data indicated that long-term treatment of melatonin and mitochondria-targeted antioxidant SkQ1 may retard an age-related decline in the adaptability of retinal cells and may be considered as a strategy to slow down AMD. At the same time effects of melatonin and SkQ1 on molecular events may be different depending on genotype and disease.

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Histological evaluation of postnatal retinal development of senescence-accelerated OXYS rats

Poster (download) Darya V. Telegina1, Anna K. Antonenko2, Oyuna S. Kozhevnikova31ICG SB RAS, Novosibirsk, Russia, telegina@bionet.nsc.ru2NSU, Novosibirsk, Russia, antonenko-98@bk.ru3ICG SB RAS, Novosibirsk, Russia, oidopova@bionet.nsc.ru De novo neurogenesis in the adult mammalian retina very limited. Thereby the structural and functional features formed during the period of maturation and formation of retina can have long-term effects on the further ontogenesis of the tissue, however, the mechanisms of these disorders remain unclear. Using model of premature aging OXYS rats we investigatedВ  the early histopathological changesВ  during postnatal retinal neurogenesis. OXYS rats spontaneously develop a retinopathy similar to age-related macular degeneration (AMD). AMD is a complex neurodegenerative disease resulting in a loss of central vision in the elderly. Ganglion, horizontal, and amacrine cells are born in the embryonic phase of rat developmen. Quantitative analysis showed decreasing amacrine cells in OXYS rats as compared Wistar rats (control). At the age of P0 and P1, the number of ganglion and horizontal cells increased in OXYS rats as compared Wistar rats. Bipolar neurons, photoreceptors and MГјller glia are born postnatally. We did not find changes in Muller cells. The number of photoreceptor\’s nuclei per column in Wistar rats increased at the age of P10 and decreased at the age of P14. In OXYS rats, maximum of number of nuclei per column accounted for age of P14 and then decreased. The number of rod bipolar neurons gradually increased by age of P14 in Wistar rats and P10 in OXYS rats. Our results indicating an alteration of retinal formation in OXYS rats during the postnatal period, which may contribute to the early development of their signs of AMD.

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